Liquid sample multi-parameter measurement system and method based on ultrasonic technology

Abstract

The invention discloses a liquid sample multi-parameter measurement system and method based on an ultrasonic technology, the system comprises a measurement water tank and a constant temperature control device used for controlling the temperature in the measurement water tank, the side wall of the measurement water tank is provided with a first clamping position, and the first clamping position is cooperatively provided with a transducer fixing device; a second clamping position is arranged on the inner wall of the measuring water tank, a sample box is installed on the second clamping position in a matched mode, during use, a liquid sample to be measured is contained in the sample box, two ultrasonic transducers are symmetrically fixed to the transducer fixing device, and the ultrasonic transducers are perpendicular to the surface of the sample box; the ultrasonic transducer is connected to the ultrasonic pulse transmitting and receiving module, the ultrasonic pulse transmitting and receiving module is connected to the data acquisition card, the data acquisition card is connected to the upper computer, and a calculation software module is arranged in the upper computer. And the upper computer is used for controlling the constant temperature control device, the ultrasonic pulse transmitting and receiving module, the data acquisition card and the calculation software module.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid parameter measurement, and in particular relates to a liquid sample multi-parameter measurement system and method based on ultrasonic technology. Background Art

[0002] Accurately measuring the physical properties of liquids, such as sound velocity, density, viscosity coefficient, acoustic attenuation coefficient, and acoustic impedance, plays a vital role in chemical production, industrial testing, medical diagnosis, and other fields.

[0003] However, traditional methods for measuring liquid physical properties, such as static sampling and laboratory analysis, often have the disadvantages of being time-consuming, inefficient and costly. In addition, these methods usually require pretreatment of liquid samples and rely on complex equipment and professional technicians to operate, which limits their application in rapid or dynamic monitoring scenarios.

[0004] Although ultrasonic measurement technology has been gradually applied due to its advantages such as non-contact, real-time and high sensitivity, existing equipment still faces many challenges in practical applications. First, existing ultrasonic measuring instruments can usually only measure a single parameter, such as sound velocity or acoustic impedance, and cannot obtain multiple liquid physical parameters at the same time, which causes the complexity and high cost of using multiple instruments to measure different parameters. Second, many current measurement technologies usually require certain known information about the composition or other physical properties of the liquid to be measured, which poses significant challenges when dealing with unknown liquid samples and limits the flexibility of practical applications. Third, the operation process of many ultrasonic devices is relatively complicated, and often requires professionally trained personnel to perform precise calibration and daily maintenance, which increases the threshold for use. Summary of the invention

[0005] The purpose of the present invention is to provide a liquid sample multi-parameter measurement system and method based on ultrasonic technology to overcome the problems of complex equipment, long measurement time, low precision, susceptibility to external interference, cumbersome operation, etc. in traditional measurement methods. The present invention can realize rapid and accurate measurement of multiple important parameters of unknown liquids, provide reliable data support for liquid property research and related applications, and improve the efficiency and quality of liquid parameter measurement.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme: A liquid sample multi-parameter measurement system based on ultrasonic technology, comprising a measuring water tank and a constant temperature control device for controlling the temperature in the measuring water tank, wherein the side wall of the measuring water tank is provided with a first clamping position, and a transducer fixing device is installed on the first clamping position, and the inner wall of the measuring water tank is provided with a second clamping position, and a sample box is installed on the second clamping position. When in use, the sample box contains a liquid sample to be measured, and two ultrasonic transducers are symmetrically fixed on the transducer fixing device, and the ultrasonic transducers are perpendicular to the surface of the sample box; The ultrasonic transducer is connected to an ultrasonic pulse transmitting and receiving module, the ultrasonic pulse transmitting and receiving module is connected to a data acquisition card, the data acquisition card is connected to a host computer, the host computer has a built-in computing software module, and the host computer is used to control the constant temperature control device, the ultrasonic pulse transmitting and receiving module, the data acquisition card and the computing software module.

[0007] Furthermore, the computing software module includes a signal processing module, a parameter computing module and a user interface.

[0008] Furthermore, the signal processing module and the parameter calculation module are implemented based on MATLAB programming, and the user interface is developed by LabVIEW. The user interface can call the signal processing module and the parameter calculation module, and display the measurement parameters and measurement results in real time.

[0009] Furthermore, the sample box includes a thick sample area, a thin sample area and an acoustic impedance measurement area, the thickness of the thick sample area is greater than that of the thin sample area, and a stainless steel block coaxial with the ultrasonic transducer is provided at the end of the acoustic impedance measurement area.

[0010] Furthermore, the side wall of the measuring water tank is symmetrically provided with two groups of first clamping positions, and the transducer fixing device includes two parallel vertical rods symmetrically provided on the two groups of first clamping positions, and the two parallel vertical rods are symmetrically provided with mounting grooves, and a horizontal cross bar is installed in the mounting groove. The two ends of the horizontal cross bar are connected by a vertical rod to form a transducer clamping device for clamping the ultrasonic transducer.

[0011] Furthermore, three groups of mounting grooves are symmetrically arranged on the two parallel vertical rods. When the horizontal cross bars are respectively arranged in the three groups of mounting grooves, the ultrasonic transducers are respectively aligned with the thick sample area, the thin sample area and the acoustic impedance measurement area.

[0012] A multi-parameter measurement method for a liquid sample based on ultrasonic technology comprises the following steps: Step 1: Pour the liquid sample to be tested into the sample box, adjust the constant temperature control device, wait for the temperature to stabilize to the set value, and start measuring; Step 2: After aligning the ultrasonic transducer with the sample box, control the transceiver mode of the ultrasonic pulse transmitting and receiving module to drive the ultrasonic transducer to collect the transmission signal and the reflection signal; Step 3: The data acquisition card performs analog-to-digital conversion on the collected signal and transmits it to the host computer; Step 4: Calculate through the built-in calculation software module of the host computer to obtain the parameters of the liquid sample to be tested.

[0013] Furthermore, the sample box includes a thick sample area, a thin sample area and an acoustic impedance measurement area, the thickness of the thick sample area is greater than that of the thin sample area, and a stainless steel block coaxial with the ultrasonic transducer is provided at the end of the acoustic impedance measurement area.

[0014] Furthermore, after aligning the ultrasonic transducer with the sample box, the transceiver mode of the ultrasonic pulse transmitting and receiving module is controlled to drive the ultrasonic transducer to collect the transmission signal and the reflection signal, specifically: The ultrasonic transducer is respectively aimed at the thick sample area and the thin sample area, and the transmission signal of the sound wave passing through the two areas is detected by the ultrasonic transducer. The ultrasonic transducer is aimed at the acoustic impedance measurement area to detect the multiple reflection signals at the interface between the stainless steel block and the liquid sample to be tested.

[0015] Furthermore, the parameters of the liquid sample to be tested are obtained by calculating through the calculation software module built into the host computer, specifically: The time difference and amplitude difference between the transmission signals are calculated by the transmission signals of the sound wave passing through the thick sample area and the thin sample area, and the sound velocity and sound attenuation coefficient of the liquid sample to be tested are obtained by using the time difference and amplitude difference; The acoustic impedance of the liquid sample to be tested is calculated by multiple reflection signals at the interface between the stainless steel block and the liquid sample to be tested, and the density of the liquid sample to be tested is calculated using the sound velocity and the acoustic impedance; The sound velocity-frequency curve and the sound attenuation coefficient-frequency curve are obtained through the spectrum information of the transmission signal of the sound wave passing through the thick sample area and the thin sample area. The viscosity coefficient of the liquid sample to be tested is calculated based on the slope of the obtained sound attenuation coefficient-frequency curve, the sound velocity and the density.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention designs a special sample box with three measurement areas, including a thick sample area, a thin sample area and an acoustic impedance measurement area, wherein the thickness of the thick sample area is greater than that of the thin sample area, and a stainless steel block coaxial with the ultrasonic transducer is provided at the end of the acoustic impedance measurement area. Based on this structural design, the sound velocity, acoustic attenuation coefficient, acoustic impedance, density and viscosity coefficient of the liquid can be measured simultaneously without changing the sample box, which greatly improves the measurement efficiency and avoids the cumbersome process of measuring each parameter separately in the traditional method.

[0017] A single sample box and a self-developed computing software module are used to achieve multi-parameter synchronous measurement, and a temperature control device is configured in the measuring water tank. The present invention can maintain high measurement accuracy and stability under different environmental conditions, meet the requirements of scientific research and industrial applications, and use ultrasonic technology for measurement to avoid damage and contamination of the liquid sample to be measured. It is particularly suitable for the analysis of precious samples and biological samples.

[0018] The user interface of the present invention can call the signal processing module and the parameter calculation module to automatically calculate the acoustic impedance, density, viscosity coefficient and other parameters of the liquid. The measurement results are displayed in real time through the user interface. The user can intuitively view various liquid parameters and record and export data as needed. The friendly interface design enables the operator to monitor and record the measurement results in real time, reducing the difficulty of operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings in the specification are used to provide further understanding of the present invention and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0020] Figure 1 It is a system structure block diagram of the present invention; Figure 2 It is a schematic diagram of the process of the present invention; Figure 3 Schematic diagram of the sample box structure of the present invention, wherein (a) is a front view of the sample box, (b) is a left view of the sample box, (c) is a top view of the sample box, and (d) is a stereoscopic view of the sample box; Figure 4 Schematic diagram of the measuring water tank structure of the present invention, wherein (a) is a front view of the measuring water tank, (b) is a left view of the measuring water tank, (c) is a top view of the measuring water tank, and (d) is a stereoscopic view of the measuring water tank; Figure 5 Schematic diagram of the structure of the transducer fixing device of the present invention, wherein (a) is a front view of the transducer fixing device, (b) is a left view of the transducer fixing device, (c) is a top view of the transducer fixing device, and (d) is a stereoscopic view of the transducer fixing device; Figure 6 This is the user interface diagram of the host computer of the present invention; Figure 7 The data are obtained by measuring 10% mass fraction salt solution, where (a) is the pulse signal in area 1, (b) is the pulse signal in area 2, (c) is the pulse signal in area 3; (d) is the measurement result.

[0021] Among them, 1 is a measuring water tank; 2 is a first clamping position; 3 is a transducer fixing device; 31 is a parallel vertical rod; 32 is a mounting groove; 33 is a horizontal crossbar; 34 is a vertical rod; 4 is a sample box; 41 is a thick sample area; 42 is a thin sample area; 43 is an acoustic impedance measurement area; 44 is a stainless steel block. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0024] Embodiment 1 See also Figure 1 , Figure 3 , Figure 4 and Figure 5 The present invention provides a liquid sample multi-parameter measurement system based on ultrasonic technology, comprising a measuring water tank 1, a sample box 4 placed in the measuring water tank 1, and a transducer fixing device 3 and a temperature control device matched with the measuring water tank 1, wherein the transducer fixing device 3 is connected to an ultrasonic transducer, the ultrasonic transducer is connected to an ultrasonic pulse transmitting and receiving module, the ultrasonic pulse transmitting and receiving module is connected to a data acquisition card, the data acquisition card is connected to a host computer, and the host computer has a built-in computing software module, which can be used to automatically collect waveform data and perform corresponding analysis and calculation.

[0025] The side wall of the measuring water tank 1 is designed with a first clamping position 2 for positioning the transducer fixing device 3 , and the inner wall of the measuring water tank 1 is designed with a second clamping position for positioning the sample box 4 .

[0026] The constant temperature control device can control the temperature in the measuring water tank to ensure that the temperature during the measuring process is controllable.

[0027] The sample box 4 is composed of a thin sample area 42, a thick sample area 41, and an acoustic impedance measurement area 43, which correspond to area 1, area 2, and area 3 respectively.

[0028] The side wall of the measuring water tank 1 is symmetrically provided with two groups of first clamping positions 2, and the transducer fixing device 3 includes two parallel vertical rods 31 symmetrically provided on the two groups of first clamping positions 2, and the two parallel vertical rods 31 are symmetrically provided with mounting grooves 32, and a horizontal cross bar 33 is installed in the mounting groove 32, and the two ends of the horizontal cross bar 33 are connected by a vertical rod 34 to form a transducer clamping device for clamping the ultrasonic transducer.

[0029] The ultrasonic pulse transmitting and receiving module drives the ultrasonic transducer to realize the collection of transmission signals and reflection signals. The data acquisition card performs analog-to-digital conversion on the collected signals and transmits them to the host computer. The calculation software module consists of a signal processing module, a parameter calculation module and a user interface. The host computer can control the constant temperature control device, the ultrasonic pulse transmitting and receiving module, the data acquisition card and the calculation software module.

[0030] The transducer fixing device 3 and the sample box 4 are positioned by using the first clamping position 2 and the second clamping position of the measuring water tank 1 to ensure that the distance between the two ultrasonic transducers is fixed and the ultrasonic transducer is perpendicular to the surface of the sample box 4 .

[0031] The width of the sample box 4 in area 1 and area 2 is different, that is, the thickness of the liquid sample to be tested is different. The transmission signal of the sound wave passing through area 1 and area 2 is detected by an ultrasonic transducer, and the time difference and amplitude difference between the transmission signals are calculated, and the sound velocity and attenuation coefficient of the liquid sample to be tested are further calculated. A stainless steel block 44 coaxial with the ultrasonic transducer is arranged on the left side of area 3. The acoustic impedance of the liquid sample to be tested is calculated by detecting multiple reflection signals at the interface between the stainless steel block 44 and the liquid sample to be tested. The calculation software module can further calculate the density of the liquid sample to be tested based on the measured sound velocity and acoustic impedance. Furthermore, the calculation software module can further calculate the viscosity coefficient of the liquid sample to be tested based on the measured sound velocity and attenuation coefficient.

[0032] The signal processing module and the parameter calculation module are implemented based on MATLAB programming, and the user interface is developed by LabVIEW. The user interface can call the signal processing module and the parameter calculation module, and display the measurement parameters and measurement results in real time.

[0033] After clicking the "Start Calculation" button in the user interface, the measurement results are obtained, specifically: The sound velocity and acoustic attenuation coefficient of the liquid sample to be tested are calculated using the time difference and amplitude difference of the ultrasonic transmission signals detected in area 1 and area 2 respectively, the acoustic impedance of the liquid sample to be tested is calculated using the multiple reflection signals detected in area 3, the density of the liquid sample to be tested is calculated using the obtained sound velocity and acoustic impedance, the sound velocity-frequency curve and the acoustic attenuation coefficient-frequency curve are obtained based on the frequency spectrum information of the ultrasonic transmission signals detected in area 1 and area 2, and the viscosity coefficient of the liquid to be tested is calculated based on the slope of the obtained acoustic attenuation coefficient-frequency curve, the sound velocity and the density.

[0034] Embodiment 2 The present invention provides a liquid sample multi-parameter measurement method based on ultrasonic technology, comprising the following steps: Step 1: Pour the liquid sample to be tested into the sample box 4, adjust the constant temperature control device, wait for the temperature to stabilize to the set value, and start measuring; Step 2: Place the horizontal crossbar 33 equipped with the ultrasonic transducer in area 1 of the sample box 4, turn on the ultrasonic pulse signal transmitting and receiving device, control the ultrasonic pulse transmitting and receiving module to the single-transmitting and single-receiving mode through the upper computer user interface, and then click the "Channel 1" button on the user interface to collect and save the ultrasonic pulse signal received at this time.

[0035] Step 3: Move the horizontal crossbar 33 equipped with the ultrasonic transducer to the area 2 of the sample box 4, and click the "Channel 2" button on the user interface to collect and save the ultrasonic pulse signal received at this time; Step 4: Move the horizontal crossbar 33 equipped with the ultrasonic transducer to the area 3 of the sample box 4. Set the ultrasonic pulse transmitting and receiving module to the self-transmitting and self-receiving mode, and then click the "Channel 3" button on the user interface to collect and save the ultrasonic pulse signal received at this time.

[0036] Step 5: Click the "Start Calculation" button on the user interface, and the system will automatically analyze the data and calculate the sound velocity, acoustic attenuation coefficient, acoustic impedance, density and viscosity coefficient. The calculation results will be displayed in real time on the user interface for users to view and record; The present invention realizes efficient measurement of the physical parameters of the liquid sample to be measured through ultrasonic technology. The present invention adopts advanced signal processing algorithms and can simultaneously obtain multiple important parameters of the liquid, such as the sound velocity, acoustic attenuation coefficient, acoustic impedance, density and viscosity coefficient.

[0037] In this embodiment, see Figure 2 , the working process of the instrument is as follows: Sample preparation: Place the liquid sample to be tested in the measuring water tank 1, and ensure that the liquid sample to be tested is stable at the set temperature through the constant temperature control device.

[0038] Ultrasonic signal transmission and reception: The ultrasonic pulse transmission and reception module is used to transmit ultrasonic pulses, and the ultrasonic signal propagates in the liquid sample to be tested and is received. This process can record the propagation time and intensity of the signal in real time.

[0039] Signal processing: Time-frequency analysis methods such as Fast Fourier Transform (FFT) and Continuous Wavelet Transform (CWT) are used to analyze the received ultrasonic signals. These methods can extract the characteristics of the signal in the time domain and frequency domain, and help identify and separate the effects of different liquid parameters on the ultrasonic signal.

[0040] Parameter extraction and calculation: By analyzing the sound velocity and sound attenuation characteristics of different liquids, using existing physical models and experimental data, the acoustic impedance, density, viscosity and other parameters of the liquid are calculated. This process improves the accuracy and efficiency of the calculation through optimization algorithms.

[0041] Results display: Finally, the measurement results are displayed in real time through the user interface. Figure 6 As shown, users can intuitively view various liquid parameters and record and export data as needed.

[0042] Figure 7 The original signals of the three measured regions are shown, where (a) is the pulse signal in region 1, (b) is the pulse signal in region 2, and (c) is the pulse signal in region 3. (1) Speed ​​of sound Figure 1 In the equation, it is assumed that the sample thickness of region 1 is d1, the sample thickness of region 2 is d2, the transducer distance is d0, and t1 and t2 are the propagation times of the ultrasonic wave through region 1 and region 2, respectively. Then, (1) (2) From formulas (1) and (2), we can get: (3) (4) Among them, Δd = d1- d2 is the difference in sample thickness at two locations, and Δt = t1- t2 is the time difference between the ultrasonic signals collected at the two locations.

[0043] (2) Sound attenuation coefficient When the sample is thick enough, there is no standing wave between the two interfaces in the direction perpendicular to the sound beam axis, and the influence of sound attenuation in water is not considered, the sound wave amplitude can be deduced as follows: (5) (6) in,A 0 is the initial amplitude of the sound wave radiated by the ultrasonic transducer, A 1 and A 2 are the ultrasonic signal amplitudes detected in the two regions, T is the amplitude loss ratio caused by the sample box wall, α 样 is the attenuation coefficient (unit: dB / cm).

[0044] Combining formulas (5) and (6), we can see that (7) Finally, the attenuation coefficient expression is: (8) (3) Acoustic impedance When the ultrasonic pulse signal is incident vertically on the interface formed by the stainless steel block 44 and the liquid to be measured, the ultrasonic wave is reflected and transmitted at the interface due to the difference in acoustic impedance of the two media. The energy of the reflected and transmitted sound waves is determined by the difference in acoustic impedance of the two media. The acoustic reflection coefficient between the two media is, (9) in, R 样 Indicates the ultrasonic reflection coefficient at the interface between stainless steel and the liquid to be tested. Z l It represents the acoustic impedance of the liquid to be measured. Z s represents the acoustic impedance of the stainless steel block 44. The acoustic impedance of the stainless steel block 44 is a known value, so only the reflection coefficient of the stainless steel block 44 and the sample interface is required to calculate the corresponding acoustic impedance coefficient and then obtain the liquid density. When the sample box 4 contains the sample to be tested, for the mth echo, its amplitude can be expressed as, (10) For the nth echo, its amplitude can be expressed as, (11) Depend on Figure 1 As shown, in region 3, A 0 represents the amplitude of the initial sound wave in the stainless steel block 44, α 钢 is the acoustic attenuation coefficient of the stainless steel block 44, L is the thickness of the stainless steel block 44. The amplitude of each echo is taken as the logarithm and then linearly fitted with the number of echoes as the dependent variable to obtain the slope of the fitting line: K The slope of the above-mentioned fitting line can be obtained by taking the logarithms of equations (10) and (11) and subtracting them. K for, (12) Take pure water as a reference, and note that the slope of the fitting line obtained from the pure water experiment is K , from formula (12), we can get: (13) in, R 水 is the reflection coefficient of the interface between the stainless steel block 44 and pure water. Therefore, the acoustic reflection coefficient of the liquid to be measured can be expressed as, (14) From equation (9) and equation (14), we can get: (15) (4) Density The acoustic characteristic impedance of the medium can be defined as, (16) in, Z l is the acoustic impedance of the medium, c It represents the propagation speed of ultrasonic wave in the medium. ρ Indicates the density of the medium.

[0045] From equation (15) and equation (16), we can get: (17) (5) Viscosity coefficient It can be deduced from the viscosity coefficient theory that: (18) For an incompressible fluid, (19) By performing wavelet transform on the collected pulse signal, we can get the corresponding change of attenuation coefficient with frequency. (20) in, α is the attenuation constant of the liquid to be measured, f is the frequency, η is the viscosity of the liquid to be measured, c is the sound velocity of the liquid to be measured, η s is the shear viscosity, η v is the bulk viscosity, ρ is the liquid density.

[0046] Embodiment 3 This embodiment uses 10% mass fraction salt solution as the experimental object.

[0047] Confirm that the experimental equipment such as the transducer fixture 3, ultrasonic pulse signal transmitting and receiving module, sample box 4, data acquisition card and user interface are in good working condition. Prepare a salt solution of the required concentration. Pour the prepared salt solution into the sample box 4 to ensure that the solution is evenly distributed and free of bubbles. Connect the 2.25MHz and 3.5MHz ultrasonic transducers to the horizontal crossbar 33, and connect the ultrasonic transducer, ultrasonic pulse transmitting and receiving module, and host computer. Place the sample box 4 in the measuring water tank 1 and open the user interface. Place the ultrasonic transducer in the measuring water tank 1 and start the ultrasonic pulse signal transmitting and receiving device.

[0048] Adjust the horizontal crossbar 33 to the ultrasonic transducer alignment area 1, adjust the ultrasonic pulse transmitting and receiving module to the single-transmitting and single-receiving mode, and click the "Channel 1" button on the user interface to collect and save the ultrasonic pulse signal received at this time. Move the horizontal crossbar 33 to the ultrasonic transducer alignment area 2, and click the "Channel 2" button on the user interface to collect and save the ultrasonic pulse signal received at this time. Switch the ultrasonic pulse signal transmitting and receiving module to the self-transmitting and self-receiving mode. Move the horizontal crossbar 33 to the ultrasonic transducer alignment area 3, adjust the ultrasonic pulse transmitting and receiving module to the self-transmitting and self-receiving mode, and click the "Channel 3" button on the user interface to collect and save the ultrasonic pulse signal received at this time. After three measurements are completed, click the "Start Calculation" button on the user interface.

[0049] To use this device to measure the relevant properties of other liquids, it is only necessary to replace the liquid sample to be tested in the sample box 4 and then repeat the steps of the third embodiment.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims of the invention.

Claims

1. A liquid sample multi-parameter measurement system based on ultrasonic technology, characterized in that: The measuring water tank (1) comprises a measuring water tank (1) and a constant temperature control device for controlling the temperature in the measuring water tank, wherein a first clamping position (2) is arranged on the side wall of the measuring water tank, a transducer fixing device (3) is mounted on the first clamping position (2), a second clamping position is arranged on the inner wall of the measuring water tank (1), a sample box (4) is mounted on the second clamping position, and when in use, a liquid sample to be tested is placed in the sample box (4), two ultrasonic transducers are symmetrically fixed on the transducer fixing device (3), and the ultrasonic transducers are perpendicular to the surface of the sample box (4); The ultrasonic transducer is connected to an ultrasonic pulse transmitting and receiving module, the ultrasonic pulse transmitting and receiving module is connected to a data acquisition card, the data acquisition card is connected to a host computer, the host computer has a built-in computing software module, and the host computer is used to control the constant temperature control device, the ultrasonic pulse transmitting and receiving module, the data acquisition card and the computing software module.

2. The liquid sample multi-parameter measurement system based on ultrasonic technology according to claim 1, characterized in that: The computing software module includes a signal processing module, a parameter computing module and a user interface.

3. The liquid sample multi-parameter measurement system based on ultrasonic technology according to claim 2, characterized in that: The signal processing module and the parameter calculation module are implemented based on MATLAB programming, and the user interface is developed by LabVIEW. The user interface can call the signal processing module and the parameter calculation module, and display the measurement parameters and measurement results in real time.

4. The liquid sample multi-parameter measurement system based on ultrasonic technology according to claim 1, characterized in that: The sample box (4) comprises a thick sample area (41), a thin sample area (42) and an acoustic impedance measurement area (43); the thickness of the thick sample area (41) is greater than the thickness of the thin sample area (42); and a stainless steel block (44) coaxial with an ultrasonic transducer is provided at the end of the acoustic impedance measurement area (43).

5. The liquid sample multi-parameter measurement system based on ultrasonic technology according to claim 4, characterized in that: The side wall of the measuring water tank (1) is symmetrically provided with two groups of first clamping positions (2), and the transducer fixing device (3) comprises two parallel vertical rods (31) symmetrically provided on the two groups of first clamping positions (2), and mounting grooves (32) are symmetrically provided on the two parallel vertical rods (31), and a horizontal cross bar (33) is installed in the mounting groove (32), and two ends of the horizontal cross bar (33) are connected to a transducer clamping device for clamping an ultrasonic transducer via vertical rods (34).

6. The liquid sample multi-parameter measurement system based on ultrasonic technology according to claim 5, characterized in that: Three groups of mounting grooves (32) are symmetrically arranged on the two parallel vertical rods (31); when the horizontal cross rods (33) are respectively arranged in the three groups of mounting grooves (32), the ultrasonic transducers are respectively aligned with the thick sample area (42), the thin sample area (42) and the acoustic impedance measurement area (43).

7. A liquid sample multi-parameter measurement method based on ultrasonic technology, based on the liquid sample multi-parameter measurement system based on ultrasonic technology according to claim 1, characterized in that: The following steps are involved: Step 1: Pour the liquid sample to be tested into the sample box (4), adjust the constant temperature control device, wait for the temperature to stabilize to the set value, and start measuring; Step 2: After aligning the ultrasonic transducer with the sample box (4), controlling the transceiver mode of the ultrasonic pulse transmitting and receiving module, and driving the ultrasonic transducer to collect the transmission signal and the reflection signal; Step 3: The data acquisition card performs analog-to-digital conversion on the collected signal and transmits it to the host computer; Step 4: Calculate through the built-in calculation software module of the host computer to obtain the parameters of the liquid sample to be tested.

8. The method for multi-parameter measurement of liquid samples based on ultrasonic technology according to claim 7, characterized in that: The sample box (4) comprises a thick sample area (41), a thin sample area (42) and an acoustic impedance measurement area (43); the thickness of the thick sample area (41) is greater than the thickness of the thin sample area (42); and a stainless steel block (44) coaxial with an ultrasonic transducer is provided at the end of the acoustic impedance measurement area (43).

9. The method for multi-parameter measurement of liquid samples based on ultrasonic technology according to claim 8, characterized in that: After the ultrasonic transducer is aligned with the sample box (4), the transceiver mode of the ultrasonic pulse transmitting and receiving module is controlled to drive the ultrasonic transducer to collect the transmission signal and the reflection signal, specifically: The ultrasonic transducer is respectively aimed at the thick sample area (41) and the thin sample area (42), and the transmission signal of the sound wave passing through the two areas is detected by the ultrasonic transducer. The ultrasonic transducer is aimed at the acoustic impedance measurement area (43) to detect multiple reflection signals at the interface between the stainless steel block (44) and the liquid sample to be measured.

10. The method for multi-parameter measurement of liquid samples based on ultrasonic technology according to claim 9, characterized in that: The parameters of the liquid sample to be tested are obtained by calculating through the calculation software module built into the host computer, specifically: Calculating the time difference and amplitude difference between the transmission signals of the sound waves passing through the thick sample area (41) and the thin sample area (42), and using the time difference and amplitude difference to obtain the sound velocity and sound attenuation coefficient of the liquid sample to be tested; Calculating the acoustic impedance of the liquid sample to be tested by multiple reflection signals at the interface between the stainless steel block (44) and the liquid sample to be tested, and obtaining the density of the liquid sample to be tested by using the sound velocity and the acoustic impedance; The sound velocity-frequency curve and the sound attenuation coefficient-frequency curve are obtained by obtaining the spectrum information of the transmission signal of the sound wave passing through the thick sample area (41) and the thin sample area (42), and the viscosity coefficient of the liquid sample to be tested is calculated based on the slope of the obtained sound attenuation coefficient-frequency curve, the sound velocity and the density.

Images